Holder for expanding workpiece



May 7, 1957 A TTORNEYS United States Patent HOLDER FOR EXPANDING WORKPIECE Robert T. Catlin, Trumbull, Conn., and Newton M. Reed,

Herkimer, N. Y., assignors to Remington Arms Company, Inc., Bridgeport, Conn., a corporation of Delaware Application May 4, 1955, Serial No. 505,999

2 Claims. (Cl. 1-44.5)

This invention relates to powder actuated tools, and contemplates an improved means for holding a disk, usually of metal, in alignment with the barrel of such tool so that a stud expelled from the barrel perforates the disk and secures it between the head of the stud and the work into which the stud is driven.

ln the drawings:

Fig. 1 is a side elevation, chiefly in section, of a typical powder actuated tool embodying the invention.

Fig. 2 is a detached sectional view of a disk retainer made in accordance with the present invention.

The invention has been illustrated as applied to a tool of the type shown in the patent to Walker, No. 2,645,772, or the patent to Catlin et al., No. 2,700,764. The prime function of tools of this type is to drive metal studs into refractory material, such as concrete, brick and the like, with a view to securing other objects to the refractory structure. Frequently, the objects to be secured are of such a nature that it is desirable to provide a disk of greater area than the stud head, which disk is penetrated by the driven stud and in the finished work is located at the surface of either the refractory structure or the object to be secured thereto. Means for supporting such a disk in alignment with the barrel is shown in the aforementioned patent to Walker as comprising a cylindrical recess in the end of a sleeve which surrounds the barrel and a spring device for holding a disk in such recess. This disk holding means has been found unsatisfactory, both by reason of the difficulty of introducing a disk therein and because of the transverse expansion of the disk as it is perforated by the stud; the force of such expansion being suiiicient to split the disk retainer and necessitate its replacement. The present invention contemplates an improved disk retainer.

Referring now to 'the drawings, the tool illustrated comprises a barrel 10, a breech block 11, and mechanism for opening and closing the breech and firing a cartridge in the barrel chamber, which will not be described here since it forms no part of the present invention. The forward part of the barrel is surrounded by a barrel sleeve 12 which is urged forwardly with respect to the barrel by a spring 13. Joined to barrel sleeve 12 is an action bar 14 which functions to prevent tiring unless the barrel sleeve is fully retracted with respect to the barrel, all as more fully described in the above-mentioned patents. Preferably, a suitable guard is provided. Numeral 15 identifies a typical guard which may be mounted on a tubular member 16 surrounding barrel sleeve 12, the guard being urged forward with respect to the tool assembly by suitable means such as spring 17.

The present invention contemplates a disk retainer, identied generally by numeral 18, in the form of a short hollow cylinder or bushing which is secured to the forward end of the barrel sleeve 12 by a suitable means such r' a 2,790,972 Patented May 7, 1957 as threads 19. Adjacent and forward from threaded section 19 of the bushing is a throat section 20 which is enlarged outwardly at a relatively small angle, say 10 to 15, preferably about 12. This throat section is dimensioned with reference to the diameter of the disk D to be retained therein, the disk having a diameter which is between the minimum and maximum diameters of the throat, so that the disk is readily inserted in the throat and is frictionally held therein by its partial peripheral engagement with the wall of the throat, as clearly shown in Fig. 2. The angle of inclination of the throat wall is so selected as to enable ready insertion of the disk and at the same time frictionally hold the disk while the tool is loaded and applied to the work. Preferably, the depth of the throat is somewhat less than the thickness of the disk, as illustrated. The bushing further comprises, adjacent the throat 20, a mouth 21 which is flared outwardly at an angle substantially greater than the throat wall angle, say 40 to 50, preferably about 45. This mouth portion not only facilitates the placement of a disk in the throat but provides a control of the disk while permitting its transverse expansion when a stud is driven through it.

Fig. l shows the tool pressed against the face of the work W and ready to fire. Springs 13 and 17 are fully compressed, and the face of bushing 18 is ush with the face of guard 15, both being securely held against the work. The disk D clears the work face by a distance comparable with the thickness of the disk.

Fig. 2 shows in broken lines the position of the disk D after it has been perforated and secured to the work face by the driven stud S. The impact and perforation of disk D by stud S overcomes the frictional force holding the disk in the throat 20 and displaces the `disk outwardly into the mouth 21, but, concurrently with such displacement, the ldisk is penetrated by the stud, so that it remains in the desired transverse position. By the time the stud has penetrated the disk a suicient amount to cause transverse expansion of the disk, the disk has moved out of the throat 20 into mouth 21, where it is not laterally confined and can expand transversely, as indicated. Thus, the enlargement of the disk does not impose any stress on any other part, and in its nal position the disk is not in gripping engagement with any other part.

What is claimed is:

l. In a powder actuated tool, the combination of a bar rel through which a stud is projected and a barrel sleeve surrounding said barrel, said barrel being longitudinally movable relative to said barrel sleeve, with a disk retainer mounted on said barrel sleeve and Adisposed to hold in alignment with said barrel a disk of given diameter to be penetrated by said stud, said disk retainer comprising an aperture having a forward wide angle entrance portion of sufficient area to permit unencumbered radial expansion of said disk when penetrated by said stud and a rearward disk holding portion having its surface slightly angled outwardly at from 10 to 15 to the axis of said barrel to join said entrance portion, an intermediate diameter of said disk holding portion being equal to the diameter of said disk.

2. In a powder actuated tool, the combination with a barrel through which a stud is projected and a barrel sleeve surrounding said barrel and mounting said barrel for relative longitudinal movement; of an annular disk retainer mounted on said sleeve and coaxially disposed in front of the muzzle of said barrel for frictionally retaining a disk of given diameter and thickness for penetration by said stud; said disk retainer having a forward face for engagement with a work surface; the interior ing portion having a surface tapering rearwardly toward the axis of said barrel at an angle of 10 to 15 to said axis, and a aring entrance portion disposed at an angle greater than 40 to said axis and joining said disk hold ing portion and said forward face; said disk holding portion having an intermediate diameter equal to the diameter of said disk and an axial length no greater than the thickness of said disk; and said entrance portion having an laxial length greater than the thickness of said disk.

References Cited in the le of this patent UNITED STATES PATENTS Temple Sept. 3,

Webster July 31,

Temple Jan. 19,

Bossong Apr. 5,

FOREIGN PATENTS Austria May 10, 

